The Pharmacokinetics Unit carries out pharmacokinetic analyses for the various drug trials taking place at KCRI. We have established protocols for measuring TB drug levels, in particular for the first line drugs Ethambutol, Rifampicin, Pyrazinamide, and Isoniazid, as well as for the second-line drug Ofloxacin. Concentration levels are measured using high performance liquid chromatography (HPLC). Drug extraction from plasma is performed using solid phase extraction (SPE).